🧪 Add AABB Contains(AABB) method and comprehensive containment unit tests

[johnstrand]

🎯 What: Added Contains(AABB) method to AABB and expanded test coverage for point and box containment.
📊 Coverage: Added unit tests covering point containment (inside, boundary, outside in all directions) and AABB containment (fully contained, identical, touching internal boundaries, partially overlapping, disjoint, and enclosing).
✨ Result: Enhanced geometric containment API and increased test coverage and reliability for AABB.

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PR created automatically by Jules for task 2834015516744845280 started by @johnstrand

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